Senate Armed Services Committee Chairman John McCain (R-AZ) on Tuesday questioned the corporate ties of President Trump's deputy defense secretary nominee Patrick Shanahan, and threatened to block the former Boeing executive's nomination if he continued to "duck" questions on the threat posed by Russia. McCain said he is "not overjoyed" with Shanahan's past experience as a former executive who spent three decades at Boeing. "I am concerned 90 percent of defense spending is in the hands of five corporations, of...